CenturyLink / Quantum Fiber Internet Review 2026
The short version: This is two wildly different services under one confusing brand. Quantum Fiber (the fiber product) is great — $30/mo for 500 Mbps symmetric, no cap, no contract. One of the cheapest fiber options in the US. CenturyLink DSL (the old copper service) is often painfully slow and should be your last resort. The brand transition from CenturyLink to Quantum Fiber makes everything confusing — check your address to see which product you'd actually get.
The Bottom Line
Quantum Fiber available? Seriously consider it. At $30/mo for 500 Mbps symmetric fiber, it's cheaper than AT&T Fiber ($55), Frontier Fiber ($40), and Verizon FiOS ($50) at comparable speeds. No cap, no contract, router included. The main downside is customer service reputation and promo pricing that expires.
Only CenturyLink DSL available? Check T-Mobile Home Internet first — it's usually faster and cheaper. If cable (Spectrum, Xfinity, Cox) is available, that's likely better too. CenturyLink DSL is often under 25 Mbps in practice, which barely supports one 4K stream. Only use DSL if you truly have no other option.
Quantum Fiber vs. AT&T Fiber: Quantum Fiber is cheaper at the entry level ($30 vs $55 for 500/300 Mbps). AT&T Fiber has more stable long-term pricing (no promo expiration). Both are good fiber services. If both serve your address, compare the prices at your specific location.
What You're Actually Getting
Lumen Technologies operates two products under two brands, and the naming is confusing. Quantum Fiber is the modern fiber-to-the-home product — symmetric speeds, no data caps, included router. Available in larger cities like Phoenix, Denver, Salt Lake City, Las Vegas, Seattle, Portland, and Minneapolis.
CenturyLink DSL is the legacy copper service. Advertised at "up to 100 Mbps" but real-world speeds are often 10–25 Mbps, especially in rural areas. Uploads top out around 10 Mbps. It's being slowly replaced by fiber, but many rural Mountain West customers are still stuck on it.
The old "Price for Life" guarantee (where your rate never increased) is mostly gone on new plans. Some grandfathered customers still have it. New Quantum Fiber plans use standard promo pricing that goes up after the intro period.
CenturyLink / Quantum Fiber Plans & Pricing
⚠️ Plan availability and pricing vary significantly by address. Fiber (Quantum Fiber) plans are only available where FTTH infrastructure has been deployed. Check your address to see which plans are offered at your location.
| Plan | Technology | Download Speed | Upload Speed | Price/mo | Contract |
|---|---|---|---|---|---|
| Simply Unlimited Internet (DSL) | DSL | Up to 100 Mbps | Up to 10 Mbps | $50 | No |
| Quantum Fiber 500 | Fiber | 500 Mbps | 500 Mbps | $30 | No |
| Quantum Fiber 1 Gig | Fiber | 1,000 Mbps | 1,000 Mbps | $50 | No |
| Quantum Fiber 2 Gig | Fiber | 2,000 Mbps | 2,000 Mbps | $75 | No |
| Quantum Fiber 8 Gig | Fiber | 8,000 Mbps | 8,000 Mbps | $165 | No |
* Quantum Fiber plans include a Wi-Fi router at no additional charge. DSL plans may require a modem rental ($15/mo) unless you supply your own compatible device. Prices are promotional rates; standard rates apply after the promotional period. All Quantum Fiber plans include unlimited data.
Availability & Coverage
CenturyLink/Lumen's network covers approximately 35 states, making it one of the most geographically widespread ISPs in the US. Its service area is especially prominent in the Mountain West (Arizona, Colorado, Nevada, Utah, Idaho, Montana, Wyoming), the Pacific Northwest (Washington, Oregon), the Upper Midwest (Minnesota, Iowa, Wisconsin, Nebraska), and parts of the South (Louisiana, Alabama, Mississippi, Tennessee).
Quantum Fiber (FTTH) is concentrated in larger cities within these states: Phoenix, Denver, Salt Lake City, Las Vegas, Seattle, Portland, Minneapolis, and others. Suburban and rural areas within the same states often receive only DSL service — sometimes at significantly lower speeds than marketed.
CenturyLink/Lumen is often the only non-cable wireline ISP available in rural Mountain West communities, where cable providers have not built infrastructure. This makes it a critical service for connectivity in those areas, even when the DSL speeds are below ideal.
Pros & Cons
✓ Pros
- Quantum Fiber: symmetric speeds up to 8 Gbps
- No data caps on Quantum Fiber plans
- No annual contracts on any plan
- Very competitive fiber pricing (500 Mbps from $30/mo)
- Wide geographic coverage — available in ~35 states
- Router included with Quantum Fiber plans
✗ Cons
- Legacy DSL is slow — often under 25 Mbps in rural areas
- Fiber availability limited to urban/suburban markets
- Customer service consistently rates below average
- Promotional pricing ends after introductory period
- Outages and reliability issues reported in some markets
- CenturyLink brand transition to Quantum Fiber can be confusing
How CenturyLink / Quantum Fiber Compares
Quantum Fiber vs. cable (Spectrum/Xfinity/Cox): Quantum Fiber wins on upload speeds (symmetric vs. 10–35 Mbps on cable) and pricing ($30/mo for 500 Mbps is hard to beat). Cable is more widely available. If both serve your address, fiber is usually the better choice.
CenturyLink DSL vs. T-Mobile Home Internet: T-Mobile wins in most cases. Faster speeds (72–245 Mbps typical vs. 10–25 Mbps real-world DSL), no data cap, same price or cheaper. If T-Mobile serves your address, try it before settling for DSL.
For rural Mountain West customers: If CenturyLink DSL is your only wired option and T-Mobile doesn't have good coverage, you may be stuck with DSL for now. Starlink ($120/mo) is an alternative if you need faster speeds, but it's expensive. Check if Quantum Fiber expansion has reached your area — Lumen is actively upgrading markets.
Check if CenturyLink / Quantum Fiber is Available at Your Address
Enter your address or ZIP code to see CenturyLink and Quantum Fiber plans and compare all available ISPs near you.
Find Plans at My Address →Frequently Asked Questions
CenturyLink vs. Quantum Fiber — what's the difference?
Same parent company (Lumen Technologies), different products. Quantum Fiber = modern fiber-to-the-home with fast symmetric speeds. CenturyLink = legacy DSL over old copper lines. Lumen is slowly rebranding everything to Quantum Fiber as they upgrade to fiber, but many areas still only have DSL. Check your address to see which you'd get.
Does Quantum Fiber have data caps?
No — unlimited data on all Quantum Fiber plans. CenturyLink DSL may have caps in some markets, so ask when signing up for DSL.
Is the "Price for Life" still a thing?
Mostly not. Grandfathered customers on older plans may still have it, but new Quantum Fiber plans use standard promo pricing that increases after the intro period. If stable pricing is important to you, AT&T Fiber is one of the few providers that doesn't hike rates after the promo.
CenturyLink DSL is the only option at my address — what should I do?
First, check T-Mobile Home Internet — it's usually faster and costs the same. If T-Mobile doesn't serve your area, check for any local cable provider. If DSL is truly your only option, the no-contract policy means you can switch the moment something better arrives. Keep checking — Quantum Fiber expansion is ongoing.
Use-Case Guides
Choosing CenturyLink or Quantum Fiber? See how it performs for your specific use case:
- Best Internet for Streaming — Quantum Fiber is excellent for streaming; legacy DSL may struggle with 4K
- Best Internet for Gaming — Quantum Fiber delivers low latency; DSL latency can be inconsistent
- Best Internet for Large Households — Quantum Fiber's symmetric gigabit speeds handle multiple users well; DSL is not ideal
- Best Internet for Working From Home — Quantum Fiber's symmetric uploads are ideal; DSL's upload speeds may limit video conferencing quality